It is not too common to find scalding hot water boiling out of the ground. This unusual phenomena is the main attraction in Yellowstone National Park. Of course, the geysers are more spectacular when they spurt a hundred or so feet into the air, but there is also a fascination with more constant and less spectacular thermal activity. I didn't really have to get too close to this bubbling pool. With a long telephoto lens, I can capture the action without the danger of getting burned.